Stretching has long been a component of the endurance athlete's warm-up routine. However, it has been shown that stretching can lead to decreased muscle stiffness and can be associated with decreased performance in force and power production. A recent study from our laboratory has shown that stretching was associated with a decrease in economy and endurance performance in trained men. PURPOSE: The purpose of this study was to investigate the acute effects of static stretching on running economy and endurance performance in trained women distance runners. METHODS: Twelve women (Height:159.4 7.4 cm; Weight: 54.8 7.2 kg; % body fat:19.7 2.8%; Age: 30 9 years) were recruited for the study and attended three laboratory sessions. On the first visit, anthropometric and maximal oxygen consumption (VO2max) (48.4 5.1 ml/kg/min) measurements were recorded. The second and third visits occurred during days 3-7 of the participants' menstrual cycle. Participants performed two sessions of 60-minute treadmill runs following a randomly assigned 18-minute static stretching protocol or 18 minutes of quiet sitting. The static stretching protocol consisted of four, 30-second repetitions of five different exercises designed to stretch the quadriceps, hamstrings, calves and gluteal muscles. During the first 30 minutes of the treadmill run (running economy), expired gases, heart rate, and rating of perceived exertion were recorded while the participant ran at 65% VO2max. During the final 30 minutes (endurance performance), distance covered, speed, heart rate, and RPE were recorded while the participant attempted to cover as much distance as possible. Repeated measures analyses were performed on the data. Significance was accepted at p < 0.05. RESULTS: Although there were significant increases in flexibility following the static stretching protocol (29.8±8.3 vs. 33.1±8.1 cm), there was no effect of stretching on VO2 (33.7±3.2 vs. 33.8±2.3 ml/kg/min), calorie expenditure (270±41 vs. 270±41 kcal), heart rate (157 10 vs. 160 12 bpm) or endurance performance (5.5 0.6 vs. 5.5 0.7 km). CONCLUSION: These findings indicated that stretching did not have an adverse effect on endurance performance in trained women, which is contrary to the findings of our previous study in men. This could mean the endurance performance decrements previously associated with stretching are not related to increases in flexibility in trained women.

Identifier:

FSU_migr_etd-2356 (IID)

Submitted Note:

A Thesis submitted to the Department of Nutrition, Food and Exercise Sciences in partial fulfillment of the requirements
for the degree of Master of Science.